Extrusion apparatus



June 3, 1952 J. A. HJULIAN 2,598,913

EXTRUSION APPARATUS Filed oct. 17, 1949 5 sheets-sheet 1 1N VEN TOR. Jzzlzz. BY

June 3, 1952 J. A. HJULIAN 2,598,913

EXTRUSION APPARATUS Filed Oct. 17, 1949 3 Sheets-Sheet 2 @D l I INVENTQR. l

Patented June 3, 1952 UNITED STATES PATENT OFFICE Julius A. Hj-ulian, Palos Heights, Il l., assigner to Crane Co., Chicago, Ill., a corporation of Illinois Application October 17, 1949, Serial No. 121,697

7 Claims. l

This invention relates to a. new and improved apparatus for the' production of cement asbestos pipe or the like by an extrusion process andv more particularly to such an apparatus adapted to operate upon a water slurry of cement and asbestos fibres or' the like and to drain a portion. of the water from the slurry and compact the residue into a dense mass.

Pipe or-` generally similar' shapes have heretofbref been made from a mortar cr slurry of cement and. asbestos by various molding and forming processes. These prior processes have numerous limitations in. that the shape produced is limited to the length and size of the`l form or mold Further, such. methods and apparatus do not lend' themselves to the making of. a hard, denseprodu'ct since adequate pressuresr are' not applied,l or the'- necessary proportion of the entrained water is not removed or both objections are present'.

While a.. cement asbestos slurry is referred. to herein. it 'is' to'- be understood that: the slurry may contain other constituents', such'. for example as colori-ng or waterproofing materials or reagents for affecting the'setting time of. the mixture.Y It will also be: understood; that. varying. proportions of nely' divided'. aggregate, such as sand, may be added. if desired and it consistent: with. the necessarystrengthrvof the product..

an object'` oi the present invention to profvid'e: a` new and improved apparatus' for' the eX- trusion of cementl asbestos pipe or ther like'.

It is: a further object. to' provide apparatus of thisl character which: provides al dense and. compactproduct..

Itf isalso anzobject' to* provide apparatus which will produce pipe or.' the like in continuous lengths..

Itis another object to provideA apparatus which is'. substantially continuous inf operation and in which the cycley of. operation. is automatically controlled..

Itis an, additional. object toprovide apparatus of. this-f character inl which substantial. portions of entrain'ed air and water are removed' from the slurry without substantial. loss 0:1.` the1 solid constituentsr Other and furtherobjects will appear as the description proceeds.v

I have shown certainV preferredv embodiments of my invention in the accompanying.' drawings, in which- Figure. 1. is a somewhat v diagrammatic layout'of the4 apparatus;l I

Figure 2 isawiring diagram of the control-circuits;

ving connected to show this pressure.

Figure 3 is a fragmentary vertical section, on an enlarged scale, showing the slurry supply and pressure apparatus;

Figure 4 is a section taken on line 4*@ of Figure 3;

Figure 5 is a View on an enlarged scale, partly in section,y ofv the pressure chamber and |brakeassembly; and

Figure 6 is a Asection taken on line 6--5 of Figure 5.

Referring first to Figure 1, the Isupply of liquid under pressure is introduced through pipe II to the hydraulic valve I2, thel pressure gauge I4? be- From the valve I2, the linev I5 leads to the left end of the pressure cylinder I8. The line I5 is shown provided With a second pressure gauge II to indicate the liquid pressure between the valve I2l and pressureh cylinder I8. The pressure cylinder I=8 contains a floating piston 20r which divides' the operating fluid chamber 22 from the' slurry-receiving portion 23 of the cylinder. The pressure cylinder I'8, as shown in Figures 3 and 5, is connectedl by port 2'4 to the passage 2'I which: leads to theslurry hopper3-I.

The pressure cylinder I8 opens into the pressure chamber 29, the right-hand end of which carriesv the brake4 assembly 35. The brake assembly35-isshownas` connected by pipe 36 topipe 31 which: leads tothe liquid chamber 2-2` in the pressure cylinder I8. The twol pipes 36: and- 3-1 are connected to a drain pipe 38 controlledl by valve 4U.V 'Ihel pipe 42 leads from the water end f 22 of the pressure cylinder I8 tothe pressurevalve 413' which: actuates the pressure switch 44;

The hydraulicv valve I2 is providedA with an exhaust connection 46. This valvel I2 is oper'- ated by means of a piston con-tained in` air cylinder 48. The lower end of air cylinder 48 is connected by pipe 49v tothe airv control` valve 50. The upper end ofthe air cylinderlld is connected by pipe 52 to the air valve 55. Solenoid Noi 1, indicated at 53, and solenoid No.` 2 indicated. at 54,. serve to reciprocate. the rod 55. This-rod has connected thereto the lever 56 which serves to' disc 66 and normally retains the valve in closed position against the valve seat. The passage 21 has a portion 69 extending upwardly into the hopper 3|, the lower part of this extension 69 being provided with lateral openings to receive material from the hopper 3|. The plunger 12 is tted into the tubular portion 69 and is connected by a tubular piston rod 13 with a piston 14 carried in cylinder 16. This cylinder is air-operated and its upper end is connected by pipe 11 to the pipe 49, as shown in Figure 1, which serves to lead air to the lower end of the hydraulic valve control cylinder 48. The lower end of cylinder 16 is connected by air pipe 19 with air pipe 52 which connects the upper end of the hydraulic valve air cylinder 48 with the air valve 50.

The inner upper end of cylinder 16 is provided with longitudinal slots 15 so that, after the disc 466 is moved downwardly by air pressure, air can move around the edge of the disc and through spider 64 against the upper face of the piston 14. The plunger 12 carries the poppet relief valves 18 normally held closed by springs 80. These valves 18 permit passage of air upon upward movement of plunger 12, which breaks any vacuum which may tend to be formed in passage 21.

Referring next to the circuit diagram of Figure 2, the |I0 volt power lines 8| and 82 are connected through fuse 83 and manual control switch-84 to the operating control switches and relays. The solenoids No. 1 and No. 2 are shown at 53 and 54 on the circuit diagram. The pressure switch 44 is also shown on this diagram, the permanently connected side of the switch being directly connected by line 86 with the manual switch 84. The switch terminal 85 is connected through the coil 86 of a delayed op'- erating relay, the other side of this coil being connected by line 81 to the opposite side 82 of the power line. The other contact 89 of pressure switch 44 is connected through line 90 to the coil 9| of a quick operating relay which serves to control solenoid No. 1 through the relay contact 92.

The construction of the brake assembly 35 of Figure 1 is shown in detail in Figures 5 and 6 in connection with the showing of the pressure chamber 29. The pressure chamber 29 contains the mandrel 95 which is supported from the spider 96 extending from the inner walls of the pressure chamber 29. This mandrel 95 isshown as provided with a water withdrawal section 99 having a plurality of narrow slitte'd'openings communicating with the inside of the mandrel. The detailed construction of this section 99 forms no part of the present invention and is fully disclosed in my co-pending application Serial No. 101,346, filed June 25, 1949.

Y The drain Vconnection |00 is provided connected to passage |0I which extends through one leg of spider 96 from the inside of mandrel section 99 for withdrawing lluid and entrained air and iinely divided solids which may pass through the slits in the section 99. It will be understood that this drain |80 may be connected to a source 'of sub-atmospheric pressure so that the withdrawal may be facilitated by suction.

. As best'shown in Figure 5, a slurry support sleeve |03 is located fitting about the mandrel V95 and within the cylindrical portion |05 of the pressure chamber assembly. `'I'his sleeve |03 comprises. two end rings |06, an outer tubular portion |01 preferably formed of rubber or similar material, and an inner body portion |08 which may be formed from a synthetic resin reinforced with textile fibres. As indicated at |09, the mandrel may have a part of its outer surfaces knurled or otherwise roughened to facilitate gripping of the compacted pipe.

The brake assembly, as shown in Figures 5 and 6, comprises a plurality of brake shoes III! which are normally held in the outer position in the housing |05. These brake shoes IIO are each provided with a pair of studs III passing upwardly through recesses ||2 in the housing. Compression springs |I4 bear against nuts I|5 carried by the studs III and also Aagainst the base of the recesses H2. The springs II4 serve to normally maintain the shoes IIIJ retracted. As shown in Figure 5, each shoe IIO is provided with a floating operating piston ||1, the piston pressing against a ball IIB which engages the outer face of the shoe I I0. Each iloating piston ||1 is provided with a cup-shaped washer |20 on its upper face, this washer being held in place by a plate I2| and bolts |23.

The pipe 36 introduces hydraulic pressure into the brake assembly and into a chamber |25, shown in Figure 6, which chamber communicates through passages |26 with the similar adjacent chambers |28. It will be understood that these chambers |28 are similarly connected to another such chamber for operating the upper brake shoe.

In the operation of the apparatus, the hopper 3| of Figure 1 will be partially filled with a supply of suitable slurry and the pipe II will be connected to a continuous source of liquid under pressure. To put the system in operation, the main switch 84, shown in Figure 2, is manually closed. There being no pressure in the water end 22, shown in Figure 1, of the pressure cylinder at this time, the pressure switch will be in position contacting the delayed relay 86, shown in Figure 2', to actuate solenoid No. 2. This moves the air valve to the position to supply air through pipe 52 to the top of air cylinder 48, thus pulling down and opening the hydraulic valve I2. Simultaneously, this air pressure is supplied through pipe 19 to the lower end `of cylinder 16, maintaining the slurry, feed mechanism in the position in which it is shownin Figure 3.

Referring again to Figure 1,V the liquid'under pressure passes through pipe I5 to valve I6, which is open to the liquid end 22 of pressure cylinder I8. This urges the floating piston 20 to the right, compressing the slurry in the pressure cylinder I8 and through the direct connection, compressing the slurry in the pressure chamber 29. As the pressure starts to build up in the pressure cylinder water end 22,.this pressure passes through lines 36 and 31v of Figure 1 to the brake assembly 35 Where, as shown in Figures 5 and 6, the pressure forces the brake shoes I I0 inwardly to grip the sleeve |03, this serving to hold the support sleeve against movement and toresist the pressure on the slurry 'and cause it to be compacted. Water from the slurry, together with entrained air and a minor portion of entrained finely divided solids, passes through the exposed slits in the drainage section 99 of the mandrel 95 and is drawn off through pipe connection |00. Y

Referring now particularly to Figures l and 2, as the pressure builds up in water pressure chamber 22.9.15 also transmitted to the pressure valve 43 which operates it to swing the switch arm 44 out of contact with the contact and into contact with the contact 89. This serves to operate the instant relay 9i' and therebyV solenoid No. l at 53 swings arm 56 to reverse the position of air valve 56'. In thisv position, air valve 50 serves to connect the air under pressure through pipe 49 to the lower end of aircylinder 48 and through pipe 11 to the upper end of cylinder 16. This air pressure forces the pistonin cylinder 48 upwardly, closing the hydraulic valve l2 so as to close oil the supply or pressure liquid to pipeV t5 and to the pressure cylinder I'8. This high pressure liquid may then be exhausted through valve l2 and exhaust pipe 46. Y

As show-n in Figure 3, at the same time the air pressure supplied to the upper end of cylinder 16 forces the disc 66 downwardly against the resistance of spring 61, disc 66 moves valve stem 63 downwardly, unseating valve 62. As disc 66 moves downward-lyl opposite grooves 15, air passes through these grooves and through spider 64 against the upper face ofpiston 14 which, through tubular piston rod 13, forces plunger 12 downwardly. This plunger 12 forces slurrydown through passage 21' and through port 24, around valve 62, into the pressure chamber P8'.

Whenpressure isreleased in the water end 22 of the pressure cylinder, it is also released behind the brake shoes H0 of Figure 5 since the chambers behind them are connected by pipes 36 and 31 to chamber 22, as shown in Figure 1. The compression springs |If4 of Figure 5 then retract the brake shoes, [l0 and thesleeve |03 is free to move to the right under the residual pressure in the system. It will be understood that the brakes are released substantially instantaneously upon drop of pressure in chamberV 22 of Figure l, while a certain amount of pressure will be maintained f0.1 a very short period of time through the slurry in, the pressure cylinder t8 and into the, pressure chamber 29, While the liquid and solids, which are the mai-n constituents ofthe slurry, are substantially non-compressible, there is a certain amount of air necessarily entrained in the slurry when it is mixed and this air is compressible. The expansion of this compressed air is a factor in supplying pressure to move the support sleeve |03 of Figure 5 to the right and, also, move the compressed slurry or formed pipe after the support sleeve |03 has left the pressure cylinder.

Considering particularly Figures 1 and 2, when the liquid pressure is reduced, another action which takes place is that pressure is reduced on a pressure valve 43 which permits the pressure switch 44 to swing back to the opposite position in engagement with contact 85. This energizes the delayed action relay 86 and solenoid No. 2. It has been found desirable to have a delayed action at this point so as to give an appreciable, though short, period of time for the movement of the slurry and formed pipe to the right, as seen in the drawings. At the end of this short delay in the actuation of solenoid No. 2, the air valve is reversed, air is supplied to the top of al1` cylinder 48 which again opens the hydraulic valve l2. At the same time, air is supplied through pipe 19 to the lower end of cylinder 16 and piston 14 is forced upwardly. As this takes place, the disc 66 is moved upwardly by the spring 61. The movement of disc 66 pulls up the valve stem 63 and closes valve 62. The upward movement of piston 14 pulls up the plunger 12, poppet valves 18 opening until the plunger clears the lower edge of openings 10. Slurry is now free to ow through these openings to rell the passage 21. Pressure again builds up in the pressure end 22 of cylinder i8 and the process continues as before. It will be understood that the body' oi slurry in hopper- 31 is not under pressure and, thus, the hopper may be reiilled from time to time without interruptingy the cycleof operation. The process of forming pipe may, therefore, be substantially continuous, although the forming action itself is intermittent, as has been described.

The specific form of constructiony show-n is to be understood to be illustrative only, as it is capable of variation to meet. differing conditions and requirements, and I contemplate such modifications as come within the spirit and scope of the appended claims.

I claim:

1. Apparatus for the extrusion ofpip'e Vor the like from a water carrying slurry which comprises a pressure chamber having an open end, means for supplying slurry to said chamber, hydraulic means for applying pressure to the slurryy inthe chamber, means for withdrawing fluid from slurry in the chamber, a brake ii-xedly located within and adjacent to the open end of the pressure chamber, said brake having radially acting opposed jaws for gripping formed material in the chamber, and means for moving the jaws into gripping position and into released position.

2. Apparatus for the extrusion of pipe or Vthe like from a water carry-ing slurrywhich comprises an elongated pressure chamber having a closed intake endl and an open discharge end, apressure cylinder having a passage connecting the cylinder to, the closed en d of the pressure chamber, means for supplying slurry to the pressure cylinder; a brake kedly located within and adjacent tothe openy end of the pressure chamber, said bra-ke havingI jaws for gripping formed material in the chamber, and means for positively movingthe jaws into gripping position and positively moving the jaws into released position.

3'. Apparatus for the extrusion of pipe orthe like from a water carrying slurry which comprises an elongated pressure chamber having a closed intake end and an open discharge end, a pressure cylinder having a passage connecting the cylinder to the closed end of the pressure chamber, means for supplying slurry to the pressure cylinder, passages for withdrawing fluid from the pressure chamber, a brake located at a xed point within and adjacent to the open end of the pressure chamber, said brake having a plurality of opposed radially movable jaws for gripping formed material, and means for reciprocating said opposed jaws in opposite directions.

4. Apparatus for the extrusion of pipe or the like from a water carrying slurry which comprises an elongated pressure chamber having a closed intake end and an open discharge end, a pressure cylinder having a passage connecting the cylinder to the closed end of the pressure chamber, means for supplying slurry to the pressure cylinder, a mandrel extending axially of the pressure chamber, passages formed in the mandrel for withdrawing fluid from the pressure chamber, a brake carried by the pressure chamber at a point adjacent its open end, said brake having radially movable jaws for gripping formed material and urging it against opposite faces of the mandrel, and means for moving said jaws into and out of gripping engagement.

5. Apparatus for the extrusion of pipe or the like from a water carrying slurry which comprises an elongated pressure chamber having a closed intake end and an open discharge end, a pressure cylinder having a passage connecting the cylinder to the closed end of the pressure chamber, a movable piston in said pressure cylinder, valve controlled connections for supplying fluid under pressure to move said piston, a slurrry supply chamber, means connecting said chamber to the pressure cylinder, means for forcing slurry from the supply chamber into the pressure cylinder, a iiuid power cylinder having a piston connected to and moving the slurry forcing means, a second fluid power cylinder having a piston connected to the valve controlling supply of uid under pressure to the pressure cylinder, means for supplying uid to the two fluid power cylinders, and means actuated by the uid pressure in the pressure cylinder for controlling the fiow of fluid to the fluid power cylinders.

6. Apparatus for the extrusion of pipe or the like from a water carrying slurry which comprises an elongated pressure chamber having a closed intake end andan open discharge end, a pressure cylinder having a passage connecting the cylinder to the closed end of the pressure chamber, a movable piston in said pressure cylinder, valve controlled connections for supplying fluid under pressure to move said n piston, a slurry supply chamber, means connecting said chamber to the pressure cylinder, means for forcing slurry from the supply chamber into the pressure cylinder, a fluid power cylinder having a piston connected to and moving the slurry forcing means, a second uidfpower cylinder having a piston connected to the valve controlling supply of uid under pressure to the pressure cylinder, means for supplying fluid to the two fluid power cylinders, movable brakes carried within and adjacent to the open end of the pressure chamber, fluid pressure means for yactuating the brakes, a connection between the brake actuating means and the uid pressure in the pressure cylinder, and means actuated by the fluid pressure in the pressure cylinder for 4 controlling the flow of uid to the fluid power cylinders.

7. Apparatus for the extrusion of pipe or the like from a water carrying slurry which comprises an elongated pressure chamber having a closed intake end and an open discharge end, a pressure cylinder having a passage connecting the cylinder to the closed end of the pressure chamber, a movable piston, in said pressure cylinder, valve controlled connections for supplying fluid under pressure to move said piston, a slurry supply chamber, means connecting said chamber to the pressure cylinder, means for forcing slurry from the supply chamber into the pressure cylinder, a uid power cylinder having a piston connected to and moving the slurry forcing means, a second fluid power cylinder having a piston connected to the valve controlling supply of uid under pressure to the pressure cylinder, means for supplying fluid to the two fluid power cylinders, radially movable brakes carried within and adjacent to the open end of the pressure chamber, fluid pressure means for actuating the brakes, a connection between the brake actuating means and the uid pressure in the pressure cylinder, a two-way switch actuated by the uid pressure in the pressure cylinder, a valve for supplying fluid to the two fluid power cylinders to alternately apply pressure and force slurry from the supply chamber, and electrical means controlled by the two-way switch for actuating said valve.

JULIUS A. HJULIAN.

REFERENCES CITED The following references Yare of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,246,048 Brown Nov. 13, 1917 1,288,496 Brosius Dec. 24, 1918 1,585,149 Humphrey May 18, 1926 

